Golf ball comprising de-vulcanized rubber

ABSTRACT

Golf balls in accordance with the principles of the present invention include a core and one or more cover layers, with the core having a base rubber component that comprises de-vulcanized rubber. The base rubber component may include a blend of polybutadiene with the de-vulcanized rubber, and may also include at least one other type of recycled material. A golf ball of the present invention exhibits performance properties similar to golf balls made using solely non-recycled base rubber as the primary component of the core. For example, a golf ball of the present invention may have a compression of between 20 and 100, and a coefficient of restitution of greater than 0.680 at a test velocity of 125 ft/s.

FIELD OF THE INVENTION

The present invention relates to the field of golf balls.

BACKGROUND OF THE INVENTION

Golf ball construction has evolved from cores having a soft center and athread winding comprised of natural rubber or synthetic polyisoprene tothe use of solid rubber cores. Currently, almost allcommercially-available golf balls include a solid rubber core. Thesecores generally comprise synthetic polybutadiene, more specifically ahigh-cis-content polybutadiene, as the base rubber of the corecomposition.

In an attempt to keep costs low, recycled material of various types havebeen incorporated into golf ball cores. Core regrind, which isvulcanized rubber spew or defect cores that are ground or pulverizedinto a fine powder, has been used for many years in the construction ofsolid golf ball cores. Scrap material from the grinding, or Glebar,process has also been used to form golf ball cores. For example, U.S.Pat. No. 6,139,447 describes the use of a vulcanized rubber powder asfiller for golf ball core compositions. U.S. Pat. No. 7,141,196describes the use of “pre-vulcanized” materials as part of the golf ballcore composition. In all cases, the use of a “recycled” material hasalways been limited to a pre-vulcanized material such as ground corescrap and Glebar/grinding dust, or pre-vulcanized materials. Further,the loading levels of the various recycled materials used in previousgolf balls has been limited because the use of high levels of loading ofeither ground core scrap, Glebar/grinding dust, or “pre-vulcanized”rubber results in an increase in the compression of the core/ball(resulting in poor feel characteristics) and decrease in the flightperformance of the golf ball. Accordingly, the use of recycledpre-vulcanized materials is inherently limited for high performance golfballs due to the negative affects (increased core/ball compression anddecreased flight performance) created by the use of such materials.

Thus, a continuing need exists for a golf ball that utilizes anincreased amount of recycled material without significantly decreasingthe performance or feel of the golf ball. What is needed is a golf ballthat improves the environment by incorporating the use of recycledrubber from environmentally destructive products such as used tires.What is also needed is an environmentally friendly, high performancegolf ball that can be produced in a cost effective manner withoutsignificantly departing from existing curing processes. A need existsfor an environmentally friendly golf ball utilizing recycled materialsthat satisfies all U.S. Golf Association golf ball requirements.

SUMMARY OF THE INVENTION

A golf ball in accordance with the principles of the present inventionincludes recycled de-vulcanized rubber as part of the base rubber of thecore, yet the ball exhibits performance properties similar to golf ballsmade using solely non-recycled base rubber as the primary component ofthe core. The use of recycled de-vulcanized rubber allows for use ofhigher levels of overall recycled materials (including ground corescrap, Glebar/grinding dust, etc.) in the golf ball core, therebyproducing a more “green,” or environmentally-friendly, golf ball.

In accordance with the principles of the present invention, the golfball has a core and one or more cover layers. The base rubber componentof the core includes a blend of polybutadiene and de-vulcanized rubber.The de-vulcanized rubber is preferably obtained through de-vulcanizationof scrap tires. For example, the recycled de-vulcanized rubber may havea Mooney viscosity of about 55±10 and a specific gravity of about 1.18to about 1.22.

The base rubber component may also include at least one other type ofrecycled material, namely recycled non-de-vulcanized rubber material(i.e., vulcanized rubber material), such as ground core scrap orGlebar/grinding dust. In certain embodiments, the core may include 1 to25 phr of the other types of recycled non-de-vulcanized rubber material.

The core may include 50 to 95 phr of a polybutadiene having a cis-1,4content of greater than 90%, 5 to 50 phr of de-vulcanized rubber, 10 to40 phr of a co-crosslinking agent, 1 to 5 phr of an activator, 0.1 to3.0 phr of a free-radical initiator, and 0 to 25 phr ofnon-de-vulcanized rubber, such as core scrap regrind or other recycledmaterial. The core suitably has a compression of between 20 and 100, anda diameter between 1.25 and 1.60 inches.

The one or more cover layers may be formed of ionomers, highlyneutralized ionomers, terpolymers, thermoplastic polyurethanes, orcombinations thereof. The outermost cover layer suitably has a Shore Dhardness of 45 to 75. The combined thickness of the cover layers ispreferably between 0.040 and 0.215 inch.

In at least one embodiment, the resulting golf ball has a diametergreater than 1.680 inches, a weight between 44.5 and 45.93 grams, acompression of between 60 and 100, and/or a coefficient of restitutionof greater than 0.680 at a test velocity of 125 ft/s.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a front view of a golf ball in accordance with apreferred embodiment of the present invention.

FIG. 2 illustrates a cross-sectional view of one embodiment of the golfball in FIG. 1.

FIG. 3 illustrates a cross-sectional view of another embodiment of thegolf ball in FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

One aspect of the present invention relates to a golf ball comprisingde-vulcanized rubber. More particularly, the golf ball includes a centeror core and one or more cover layers, with the de-vulcanized rubberpresent in the core.

Vulcanization refers to a specific curing process of rubber involvinghigh heat and the addition of sulfur or other equivalent curatives.Uncured natural rubber is sticky and can easily deform when warm, and isbrittle when cold. Vulcanization is a chemical process in which polymermolecules are linked to other polymer molecules by atomic bridgescomposed of sulfur atoms or carbon to carbon bonds. The end result isthat the springy rubber molecules become cross-linked to a greater orlesser extent. This makes the bulk material harder, much more durableand also more resistant to chemical attack. It also makes the surface ofthe material smoother and prevents it from sticking to metal or plasticchemical catalysts. Conventional products produced of vulcanized rubberinclude hockey pucks, tires, shoe soles and hoses.

Referring to FIGS. 1-3, a golf ball is indicated generally at 10. FIG. 2illustrates the golf ball 10 having a core 12 and a one-piece coverlayer 14, whereas FIG. 3 illustrates the golf ball 10 having a core 12and a two-piece cover layer 14, 16. In any case, the core 12 comprisesde-vulcanized rubber as part of the base rubber of the core 12.Vulcanization is generally considered to be an irreversible process,similar to other thermosets and is contrasted strongly withthermoplastic processes. However, recent material advancements allow forde-vulcanized recycled rubber material. The golf ball 10 exhibitsperformance properties similar to golf balls made using solelynon-recycled base rubber as the primary component of the core. The useof recycled de-vulcanized rubber does not result in a harder core, as isobserved when high levels of regrind/recycled vulcanized fillermaterials are added to core compositions. Additionally, the use ofrecycled de-vulcanized rubber does not require significant changes orincreases to the curative package of the rubber core that is necessarywhen vulcanized rubber powders or pre-vulcanized rubber materials areadded to golf ball core compositions. Furthermore, the use of thede-vulcanized tire rubber allows for use of higher levels of overallrecycled materials (including ground core scrap, Glebar/grinding dust,etc.) in the golf ball core, thereby making a more “green” orenvironmentally-friendly golf ball.

More specifically, the golf ball core 12 comprises a blend of a highcis-1,4-polybutadiene rubber and de-vulcanized recycled, or “reclaimed,”tire rubber as the base rubber material. For example, the base rubbercomponent of the core composition may include between 50 and 99 phr ofthe high cis-1,4-polybutadiene rubber and between 1 and 50 phr ofde-vulcanized rubber, such that the core 12 itself includes 50 to 95 phrof the high cis-1,4-polybutadiene rubber and 5 to 50 phr of thede-vulcanized rubber.

The core 12 is formulated using a blend of the base rubber material, aco-crosslinking agent, a free-radical initiator, and fillers asnecessary to provide acceptable compression, density, and resilience.More particularly, the core 12 may include 10 to 40 phr of theco-crosslinking agent, optionally 1 to 5 phr of an activator such aszinc oxide, and 0.1 to 3.0 or 0.1 to 2.0 phr of the free-radicalinitiator.

The cis-1,4 content of the polybutadiene is preferably greater than 90%,or greater than 94%. Polybutadiene rubber suitable for use in the core12 can be synthesized using nickel, cobalt, or neodymium catalysts, forexample. Commercially-available examples of polybutadiene materials madeusing neodymium catalyzed materials include Europrene® NEOCIS® BR-40,produced by Polimeri Europa, and Neodene® BR-40, produced by Karbochem.Commercially-available examples of polybutadiene materials made usingnickel catalyzed materials include Budene® 1207, produced by theGoodyear Tire and Rubber Company, and Kumho® KBR-01, produced by KumhoTire and Rubber.

The de-vulcanized rubber material is preferably obtained throughde-vulcanization of scrap tires. The recycled tire rubber is obtainedfrom a process including the following steps:

Grinding/smashing of old tires to break the tires into small pieces.

A magnetic separation step to remove any metal material from the tirescrap.

A further grinding step to reduce the scrap tire rubber into fineparticles.

A de-vulcanization step to break down crosslinks from the scrap rubberand revert it to a curable state.

A refining/forming step to form the de-vulcanized tire rubber into asolid/bale form for ease of handling/processing.

Detailed descriptions of procedures for de-vulcanization of tire rubberare illustrated in the following issued U.S. patents: U.S. Pat. No.5,602,186, U.S. Pat. No. 5,798,394, U.S. Pat. No. 5,955,035, U.S. Pat.No. 6,095,440, U.S. Pat. No. 6,387,966, U.S. Pat. No. 6,416,705, U.S.Pat. No. 6,541,526, U.S. Pat. No. 6,548,560, and U.S. Pat. No.6,992,116, each of which is incorporated herein by reference in itsentirety.

One example of de-vulcanized tire rubber suitable for use in the golfballs of this invention is produced (“reclaimed”) by Yaw Shuenn Ind.Co., Ltd. In particular, one preferred material is YS100 reclaimedrubber, a de-vulcanized tire rubber having a Mooney viscosity of about55±10 and a specific gravity of about 1.18 to about 1.22.

The co-crosslinking agent may be any suitable agent known in the art,such as metal salts of acrylate esters. The co-crosslinking agent ispreferably a zinc salt of an unsaturated acrylate ester. Zinc diacrylateis a preferred metal salt. Additionally, the co-crosslinking agent mayinclude a level of fatty acid salt of up to 10% of the totalco-crosslinking agent. For example, a level of about 7% to 10% of afatty acid salt such as zinc stearate or zinc palmatate may bepreferred. Commercially-available materials suitable for use as theco-crosslinking agent are produced by Sartomer, Inc. and Kuo ChingChemical Company, Limited, for example.

Any free-radical initiator known in the art may be utilized, includingbut not limited to peroxides. In particular, peroxides such as dicumylperoxide, tert-butyl peroxybenzoate, butyl 4,4′-di-(tert-butylperoxy)valerate, and 1,1-di-(tert-butylperoxy)-3,3,5-trimethylcyclohexane aresuitable for use. Commercially-available free-radical initiatorssuitable for use in the core 12 include dicumyl peroxide, sold by AkzoNobel Chemicals under the trade name Percadox BC, and1,1-di-(tert-butylperoxy)-3,3,5-trimethylcyclohexane, sold by Akzo NobelChemicals under the trade name Trigonox® 29/40 and Trigonox® 29A-88.

Fillers suitable for use in adjusting the density of the core 12 toachieve a desired weight may be either inorganic or organic materials.Preferred materials for adjusting the density of the core 12 includeinorganic materials such as zinc oxide, barium sulfate, titaniumdioxide, calcium carbonate, magnesium carbonate, and mixtures thereof.

In addition to the de-vulcanized rubber material, the core 12 may alsoinclude one or more other types of non-de-vulcanized (i.e., vulcanized)recycled materials, such as core scrap regrind and Glebar/grinding dust.In particular, the core 12 may include 0 to 25 phr, or in certainembodiments 1 to 25 phr, of vulcanized recycled material.

The core 12 preferably has a diameter between 1.25 and 1.60 inches, adensity between 1.10 and 1.30, and a compression of between 20 and 100.

As noted above, the cover layer may include one or more separate layers14, 16, which may have differing compositions and properties so as tomaximize the desired qualities of the golf ball 10 of the invention.Materials suitable for forming the cover layers include, but are notlimited to, ionomers, highly neutralized ionomers (such as 100%neutralized ionomers), terpolymers, polyurethanes, polyesters,polyolefins, ethylene-methacrylic acid copolymers, ethylene-acrylic acidcopolymers, and combinations thereof. One example of acommercially-available cover layer material is a family of co- orterpolymers manufactured by DuPont under the trade name DuPont HPF®.These terpolymers comprise ethylene, acrylic acid, and in oneembodiment, n-butyl-acrylate; preferably 100% of the terpolymers' acidgroups are neutralized with metal ions.

The outermost cover layer 14/16 of the golf ball 10 (layer 14 in FIG. 2,layer 16 in FIG. 3) has a surface comprising numerous dimples, such asbetween 250 and 500 dimples, and the surface of the ball 10 ispreferably coated with a protective coating comprising either aurethane-based paint system or an acrylic-based paint system. Theoutermost cover layer 14/16 has a Shore D hardness between 45 and 75,and a combined thickness of all cover layers 14, 16 is preferablybetween 0.040 and 0.215 inch.

The United States Golf Association (U.S.G.A.) has specific requirementsfor golf ball performance. See “The Rules of Golf” as approved by theUnited States Golf Association, Appendix III—Effective Jan. 1, 2008.These requirements are designed to limit the performance of the golfball. The currently proscribed requirements for a golf ball to be listedfor play in a U.S.G.A. sanctioned event include a maximum weight of 1.62oz. (45.93 grams) and a minimum diameter of 1.68 in (42.67 mm). Thus,the golf ball 10 of the invention suitably has a diameter of at least1.680 inches, and a weight between 44.5 and 45.93 grams. Furthermore,the golf ball 10 suitably has a Shore D hardness (as measured on thecurved surface of the ball) of between 45 and 75, a compression ofbetween 60 and 100, and a coefficient of restitution (at a test velocityof 125 ft/s) of greater than 0.680.

EXAMPLES

Golf balls using de-vulcanized rubber as a portion of the rubbercomponent of the core 12 were made as set forth below.

Cores for the invention were mixed according to the formulas specifiedin Table 1. Three different levels of de-vulcanized rubber content wereused. These three test cores were compared to a conventional golf ballcore (Example C-1). Properties of the cores made using various levels ofde-vulcanized rubber, as well as properties of the conventional core,are also included in Table 1.

TABLE 1 Core Formulas/Properties Material 1 2 3 C-1 Karbochem Neodene-4090 80 60 100 YS100 Reclaimed Rubber 10 20 40 — Sartomer SR416D ZDA 27 2727 27 Zinc Oxide 5 5 5 5 Stearic Acid 6 6 6 6 Barium Sulfate 18 18 18 18Trigonox 29/40 1.75 1.75 1.75 1.75 Diameter (inches) 1.539″ 1.540″1.540″ 1.544″ Weight (grams) 37.01 37.49 37.61 36.63 Deflection (200 lb.load) 0.1012″ 0.1022″ 0.0999″ 0.1053″ Compression (ADC)* 78.8 77.8 80.174.7 C.O.R. (125 ft/s) 0.786 0.766 0.719 0.800 *Compression for golfball cores is measured using ADC compression tester.

-   Karbochem Neodene 40 is a neodymium catalyzed high-cis content    polybutadiene rubber produced by Karbochem (PTY) Ltd.-   YS100 Reclaimed Rubber is a de-vulcanized tire rubber produced by    Yaw Shuenn Ind. Co., Ltd.-   Sartomer® SR416D is a Zinc Diacrylate (92% ZDA level) produced by    Sartomer Corporation.-   Trigonox® 29/40 is 1,1-Di-(t-butylperoxy)-3,3,5-trimethylcyclohexane    (40% active) produced by Akzo Nobel Chemicals, Inc.

An analysis of the properties of the molded cores of Examples 1 through3 as compared to the conventional golf ball core (Example C-1) follows:

Example 1

Core Example 1 includes a blend of 90 phr Neodene 40 and 10 phr ofde-vulcanized tire rubber. The resultant core has comparable compressionand slightly reduced coefficient of restitution (C.O.R.) compared tocontrol core C-1. A decrease in C.O.R. of about 0.014 is observed.

Example 2

Core Example 2 includes a blend of 80 phr Neodene 40 and 20 phr ofde-vulcanized tire rubber. The resultant core has comparable compressionand lower C.O.R. compared to control core C-1. A decrease in C.O.R. ofabout 0.034 is observed.

Example 3

Core Example 3 includes a blend of 60 phr Neodene 40 and 40 phr ofde-vulcanized tire rubber. The resultant core exhibits an increase incompression of about 6 points and a lower C.O.R. of about 0.081 comparedto control core C-1.

The golf ball cores described in Table 1 demonstrate that the use of thede-vulcanized tire rubber does not have a significant effect on ballcompression. There is a decrease observed in C.O.R., as for every 10 phrof high-cis polybutadiene replaced with de-vulcanized rubber a decreaseof about 0.016 in C.O.R. is observed.

Golf balls were molded with cores 5 and 6 according to the formulasspecified in Table 2, and with Value and Range cover layers as describedin Table 3.

TABLE 2 Core Formulas/Properties Material 5 6 Karbochem Neodene-40 90 80YS100 Reclaimed Rubber 10 20 K-Cure 339 ZDA 27 27 Zinc Oxide 5 5 StearicAcid 6 6 Barium Sulfate 14.5 11 Trigonox 29A-88 1.75 1.75 Diameter(inches) 1.541″ 1.540″ Weight (grams) 36.76 36.70 Deflection (200 lb.load) 0.104″ 0.1033″ Compression (ADC) 79.6 76.7 C.O.R. (125 ft/s) 0.7810.764

-   K-Cure 339 is a Zinc Diacrylate (92% ZDA level) produced by Kuo    Ching Chemical Company, Limited.-   Trigonox® 29A-88 is    1,1-di-(t-butylperoxy)-3,3,5-trimethylcyclohexane (88% active)    produced by Akzo Nobel Chemicals, Inc.

TABLE 3 Golf Ball Cover Formulations Cover ID Formula Value Iotek8030/Iotek 7010 @ 50/50 Range Surlyn 8940/Surlyn 9910/Surlyn 8320 @33/33/34

-   Iotek® 8030 is a copolymer comprising ˜85% by weight of ethylene and    ˜15% by weight of acrylic acid. Approximately 35% of the acrylic    acid groups are neutralized with sodium ions.-   Iotek® 7010 is a copolymer comprising ˜85% by weight of ethylene and    ˜15% by weight of acrylic acid. Approximately 35% of the acrylic    acid groups are neutralized with zinc ions.-   Surlyn® 8940 is a copolymer comprising ˜85% by weight of ethylene    and ˜15% by weight of methacrylic acid. Approximately 29% of the    methacrylic acid groups are neutralized with sodium ions.-   Surlyn® 9910 is a copolymer comprising ˜85% by weight of ethylene    and ˜15% by weight of methacrylic acid. Approximately 58% of the    methacrylic acid groups are neutralized with zinc ions.-   Surlyn® 8320 is a terpolymer comprising ˜67-70% by weight of    ethylene, ˜10% by weight of methacrylic acid, and ˜20-23% by weight    of n-butyl acrylate. Approximately 55% of the methacrylic acid    groups are neutralized with sodium ions.-   Surlyn® ionomers described above are produced by E.I. duPont de    Nemours and Company.-   Iotek® ionomers described above are produced by ExxonMobil    Chemicals, Inc.

Golf balls were formed of various combinations of cores 5 and 6 fromTable 2 and core C-1 from Table 1 with the cover layer formulations fromTable 3. Properties of the resulting balls are provided in Table 4.

TABLE 4 Golf Ball Properties EX-1 EX-2 EX-3 C-R C-V Core 5 6 6 C-1 C-1Cover Range Range Value Range Value Ball Physical Properties Size (in.)1.6866″ 1.6854″ 1.6881″ 1.6879″ 1.6874″ Weight 45.53 45.38 45.43 45.7145.66 (grams) Compression 87.5 86.6 89.8 86.5 92.4 C.O.R. 0.729 0.7100.724 0.734 0.724 (175 ft/s) Impact Dur. 73.7 97.4 70.1 66.8 50.9 (175ft/s)+ Ball Flight Properties Carry (yd.) 250.5 249.7 250.7 252.4 253.1Total (yd.) 269.7 267.7 271.8 271.1 275.2 Max Height 29.6 30.2 28.2 29.428.9 (yd.) Spin (rpm) 2701 2693 2726 2698 2675 Ball Velocity 152.5 151.9153.0 153.0 154.4 (mph) +Impact durability tested by shooting balls intoa steel plate at a test velocity of 175 ft/s. The number of hits untilfailure is noted.

An analysis of the properties of cores 5, 6, and C-1 in combination withthe Value and Range cover layers follows:

Example EX-1

The golf ball of Example EX-1 was molded using core 5 (comprising 10 phrde-vulcanized rubber loading) and Range cover (Surlyn® ionomer blend).The resultant ball had compression comparable to the range control ballC-R. The golf ball of Example EX-1 exhibited lower C.O.R. than thecontrol range ball, and a decrease in ball velocity of about 0.6 mphcompared to range control C-R. However, only a minimal decrease in balldistance (less than 2 yards) was observed. The golf ball of Example EX-2also exhibits a slight increase in impact durability (hits to failure)of about 10% compared to the range control C-R.

Example EX-2

The golf ball of Example EX-2 was molded using core 6 (comprising 20 phrde-vulcanized rubber loading) and Range cover (Surlyn® ionomer blend).The resultant ball had compression comparable to the range control ballC-R. The golf ball of Example EX-2 exhibited lower C.O.R. than thecontrol range ball, and a decrease in ball velocity of about 1.1 mphcompared to range control C-R. However, only a minimal decrease in balldistance (less than 3 yards) was observed. The golf ball of Example EX-2also exhibits an increase in impact durability (hits to failure) ofabout 40% compared to the range control C-R.

Example EX-3

The golf ball of Example EX-3 was molded using core 6 (comprising 20 phrde-vulcanized rubber loading) and Value cover (Iotek® ionomer blend).The resultant ball had compression comparable to the value control ballC-V. The golf ball of Example EX-3 exhibited the same C.O.R. as thevalue control ball C-V, and a decrease in ball velocity of about 1.4 mphcompared to value control ball C-V. However, only a minimal decrease inball distance (less than 3 yards) was observed. As observed on the rangeball example (Example EX-2), the value ball of Example EX-3 alsoexhibits an increase of roughly 40% in impact durability.

Overall, the addition of de-vulcanized tire rubber to the corecomposition results in a loss (or no change) in C.O.R., but minimal lossin flight distance performance. The addition of the de-vulcanized tirerubber to the core also results in a significant increase in the impactdurability of the golf ball.

It should be understood that various changes and modifications to thepreferred embodiments described herein would be apparent to thoseskilled in the art. Such changes and modifications can be made withoutdeparting from the spirit and scope of the present invention and withoutdemising its attendant advantages. It is therefore intended that suchchanges and modifications be covered by the appended claims.

1. A golf ball comprising: a core; and one or more cover layers, thecore comprising a blend of polybutadiene and de-vulcanized rubber as abase rubber component, the golf ball configured to meet the golf ballrequirements of The Rules of Golf provided by the U.S. Golf Association.2. The golf ball of claim 1, wherein the de-vulcanized rubber isobtained through de-vulcanization of scrap tires.
 3. The golf ball ofclaim 1, wherein the de-vulcanized rubber has a Mooney viscosity ofabout 55±10 and a specific gravity of about 1.18 to about 1.22.
 4. Thegolf ball of claim 1, wherein the core comprises 50 to 95 phr of apolybutadiene having a cis-1,4 content of greater than 90%; 5 to 50 phrof de-vulcanized rubber; 10 to 40 phr of a co-crosslinking agent; 1 to 5phr of an activator; 0.1 to 3.0 phr of a free-radical initiator; and 0to 25 phr of core scrap regrind.
 5. The golf ball of claim 1, whereinthe core has a compression of between 20 and
 100. 6. The golf ball ofclaim 1, wherein the core has a diameter between 1.25 and 1.60 inches.7. The golf ball of claim 1, wherein the one or more cover layerscomprise a material selected from the group consisting of ionomers,highly neutralized ionomers, terpolymers, thermoplastic polyurethanes,and combinations thereof.
 8. The golf ball of claim 1, wherein anoutermost cover layer has a Shore D hardness of 45 to
 75. 9. The golfball of claim 1, wherein the golf ball has a diameter greater than 1.680inches.
 10. The golf ball of claim 1, wherein the golf ball has a weightbetween 44.5 and 45.93 grams.
 11. The golf ball of claim 1, wherein thegolf ball has a compression of between 60 and
 100. 12. The golf ball ofclaim 1, wherein the golf ball has a coefficient of restitution ofgreater than 0.680 at a test velocity of 125 ft/s.
 13. A golf ballcomprising: a core; and at least one cover layer, the core comprising abase rubber component that includes a blend of polybutadiene, recycledde-vulcanized rubber, and at least one other type of recycled material.14. The golf ball of claim 13, wherein the core comprises 50 to 95 phrof a polybutadiene having a cis-1,4 content of greater than 90%; 5 to 50phr of de-vulcanized rubber; and 1 to 25 phr of the at least one othertype of recycled material.
 15. The golf ball of claim 13, wherein the atleast one other type of recycled material comprises at least one of thegroup consisting of ground core scrap and Glebar/grinding dust.
 16. Thegolf ball of claim 13, wherein the de-vulcanized rubber is obtainedthrough de-vulcanization of scrap tires.
 17. The golf ball of claim 13,wherein the at least one cover layer has a Shore D hardness between 45and 75 and a combined thickness of between 0.040 and 0.215 inch, andcomprises at least one of the group consisting of ionomers, highlyneutralized ionomers, terpolymers, thermoplastic polyurethanes, andcombinations thereof.
 18. The golf ball of claim 13, wherein the golfball has a compression of between 60 and
 100. 19. The golf ball of claim13, wherein the golf ball has a coefficient of restitution of greaterthan 0.680 at a test velocity of 125 ft/s.
 20. A golf ball comprising: acore having a base rubber component comprising de-vulcanized rubber; andat least one cover layer; wherein the core has a compression of between20 and 100, and the golf ball has a coefficient of restitution ofgreater than 0.680 at a test velocity of 125 ft/s.
 21. The golf ball ofclaim 20, wherein the de-vulcanized rubber is obtained throughde-vulcanization of scrap tires.
 22. The golf ball of claim 20, whereinthe core further comprises recycled non-de-vulcanized rubber material.23. The golf ball of claim 22, wherein the recycled non-de-vulcanizedrubber material comprises at least one of the group consisting of groundcore scrap and Glebar/grinding dust.
 24. The golf ball of claim 20,wherein the core comprises 50 to 95 phr of a polybutadiene having acis-1,4 content of greater than 90%; 5 to 50 phr of de-vulcanizedrubber; and 0 to 25 phr of recycled non-de-vulcanized rubber material.25. The golf ball of claim 20, wherein the core has a diameter of 1.25to 1.60 inches.
 26. The golf ball of claim 20, wherein an outermostcover layer has a Shore D hardness of 45 to
 75. 27. The golf ball ofclaim 20, wherein the golf ball has a diameter greater than 1.680inches.
 28. The golf ball of claim 20, wherein the golf ball has aweight between 44.5 and 45.93 grams.
 29. The golf ball of claim 20,wherein the golf ball has a compression of between 60 and 100.